Pilot – June 2018

70 | Pilot June 2018 | pilotweb.aero

Feature | Building a Wot

Wing rib production has now
reached the halfway mark and I’m
getting up a little more speed. You
can picture me, classical music
on the radio, doing my daily
hour or two, drawing out endless
rows of biscuits on thin plywood,
cutting out a strip of them with
the Stanley knife. Then donning
ear protection and slicing up the
strip with the bandsaw. (John
Urmston reportedly cut them up
with scissors, which doesn’t work
for me.) Steaming rib booms
and clamping them to leave
overnight so that in the morning
they’re nicely curved and bone
dry. Fitting the booms into the
rib jig, making repeated passes of
both ends over bench sander and
band saw until they fit perfectly.
Cutting a ‘pea stick’ bit by bit into
sections, sawing and sanding
each section until it just fits,
butting nicely against the booms
to make the required lattice work.
Once a rib and its biscuits are
ready for gluing, everything
speeds up. The first batch of
glue only takes me a third
along the rib before it starts to
get gummy, then I whip up a
second batch. Each glue joint is
followed by a pre-sanded biscuit
and each biscuit requires up to
four carefully positioned staples
to clamp it down. Usually I get
it all done after whipping up a

third batch of glue and then prise

out the rib. So far the ribs have

always come out in one piece. A

quick clean of the jig removes any

glue that got left behind. When

I return to the rib the next day,

everything is calm again. First,

prise out the staples. Second,

have a good look at all the joints

to make sure they’re sound.

Finally, glue biscuits on the other

side of the rib, clamping them

with butterfly clamps. And then

on to the next rib.

Soon I’ll be getting on to my

inspector, chivvying him to make

up the rest of the wing cutting list.

He will get around to it eventually.

And there’s no shortage of other

things I can be doing in the

meantime. I will order some more

sheet steel from LAS Aerospace,

and get back to manufacturing

multitudinous metal fittings.

I suppose a day will come,

perhaps a decade from now (by

which time I’ll be in my mid-

seventies) when the tempo will

quicken. I might even briefly move

into the centre lane. There will be

big sums to spend on engine and

instruments (emphatically not

new−everything second-hand,

or costs will overrun), an endless

series of orders and deliveries

for the thousands of nuts, bolts,

washers and other bits. A fuel

tank to make, undercarriage,

interplane struts, goodness me,

another engine cowling (the last

one took fully three months). And

then gluing on fabric, stitching, rib

tapes, priming, painting, snipping

control cables and bracing cables

to length, adjusting turnbuckles,

and a thousand-and-one details.

Not to mention LAA paperwork

and test-flying.

I’ll cope with it when it comes.

For now, it’s one rib at a time. Life

in the slow lane.

Each glue

joint is

followed

by a pre-

sanded

biscuit

Nick’s LAA inspector praised his handiwork “You should see the state of some of the factory-produced ones...”

Looking ready to cover, the assembled tailplane